I think the best is to rent an entire set for a short period and try them out.
Say, D700 + 14-24, 24-120, and 70-200.
Despite a small investment, obtaining your own experience is probably more
accurate than anything else.
I would concur this sentiment... Play with the equipment first before you jump ship so you dont have buyers remorse later. Like you i use CPS and canon service regularly, (gold member)... CPS has worked with me in the past given me whatever loaner gear I requested whenever I requested it and when I've called for support they have been more than willing to help... That being said, there's a lot of room to be improved such as email support (they sometimes reply to me via email, other time not) and communication during service work... I usually get an email when they confirm they are STARTING work, not when received which can be 24 hours afterwards, and an email after it ships... almost all my service work was done within 24 hours from when they start and also while they claim they will ship it to you via 2 day service, 9 out of 10 times for me, they ship it overnight for free...
Is CPS perfect? No. Will they cater to your every whim and email or kiss your butt? Nope. For what they offer and cost, is it more than acceptable? Sure... For full disclosure, what issues do you have with CPS to give you a bad experience? With the AF problems, even with the 1d4, you said you were initially impressed but overall not content... how so? Can you elaborate so we can best help? The 5D AF is the primary reason why i wont consider upgrading from the 7D to the 5D MII... If the 5D MIII has the 7D AF or better, I will upgrade in a heartbeat.